Convex Mirror

Francesco one day set himself
To take his own portrait, looking at himself from that purpose
In a convex mirror, such as is used by barbers . . .
He accordingly caused a ball of wood to be made
By a turner, and having divided it in half and
Brought it to the size of the mirror, he set himself
With great art to copy all that he saw in the glass,"
Chiefly his reflection, of which the portrait
Is the reflection, of which the portrait
Is the reflection once removed.

-John Ashbery, Self Portrait in a Convex Mirror

Besides this, in order to investigate the subtleties of art, he set himself one day to make his own portrait, looking at himself in a convex barber's mirror. And in doing this, perceiving the bizarre effects produced by the roundness of the mirror, which twists the beams of a ceiling into strange curves, and makes the doors and other parts of buildings recede in an extraordinary manner, the idea came to him to amuse himself by counterfeiting everything. Thereupon he had a ball of wood made by a turner, and, dividing it in half so as to make it the same in size and shape as the mirror, set to work to counterfeit on it with supreme art all that he saw in the glass, and particularly his own self, which he did with such lifelike reality as could not be imagined or believed.

Now everything that is near the mirror is magnified, and all that is at a distance is diminished, and thus he made the hand engaged in drawing somewhat large, as the mirror showed it, and so marvelous that it seemed to be his very own.